The recession is giving rise to a new crop of rip-off ratings consultants which promises to get worse with the onset of the 2010 revaluation and business rates draft list which comes out this October, says a rates expert.

The complexity of the legislation surrounding business rates - coupled this year with the government's confusing new scheme which will enable payers to defer payment of 60% of the increase in their 2009/10 bills over the next three years - means that many retailers will succumb to persuasive cold-calling cowboy consultants.

The last three revaluations, dating back to 1995, have seen a proliferation of consultants conning retailers with promises of rates reductions, who have then disappeared with the money they were paid upfront.

"It seems these companies have spotted a killing to make," said chartered surveyor and ratings consultant Ken Batty.

"Retailers must avoid calls from call centres and personal visits from cold-callers and deal only with practices where quite clearly the chartered surveyors are experienced in rating and are members of the Royal Institution of Chartered Surveyors (RICS), and preferably also members of the Institute of Revenues Rating and Valuation and the Ratings Surveyors Association."

Batty said that recent worrying trends include call centre companies with no real expertise - except in persuasive patter - hiring chartered surveyors (known as factoring out) for a flat fee. "Do not go through third parties," he warned.

"Bona fide business rates consultants will not ask for upfront fees. Beware phrases like 'no money to pay until your appeal is accepted'. All appeals are accepted and you can do it yourself online."